In October, the Walt Disney Company's television network, ABC, and Disney's cable network began offering five television shows for download via iTunes.

Apple said Tuesday that it has now sold more than 3 million videos from its iTunes store since launching the feature in early October, indicating that customer demand extended beyond simple one-time curiosity.

"It has continued growing, and at a faster pace than when we started," said Eddie Cue, Apple's vice president of iTunes. "It's not like people are downloading once and not coming back."

Other shows now offered for download include the 1980s hit "Knight Rider," "Alfred Hitchcock Presents," and the recent remake of "Battlestar Galactica." Most of the older shows will initially offer only the first season, but later seasons will be added over time, Cue said.